The induced electromotive force obtained from a time variation of the magnetic field of electromagnetic waves using Faraday's law is generated in proportion to the number of winds of an induction coil and a time variation of flux linkage. However, the intensity of the magnetic field is abruptly decreased in response to a distance from an electromagnetic wave generating source. Thus, the induced electromotive force is hardly induced to the induction coil at more than a predetermined distance so that energy according to wireless power conversion cannot be obtained. Furthermore, the induction coil must be disposed within a very short range from the electromagnetic wave generating source in a prior art so that its installation position is greatly restricted or it cannot be installed because of its bad appearance.